Herbicidal 5-(2-chloro-4-trifluoromethyl)-phenoxy-2-nitrobenzoic acid and salts thereof, and various herbicidal derivatives of these compounds have been proposed including alkyl and cycloalkyl esters, alkylthio esters, phenyl ester, alkyl and dialkyl amido and benzoyl chloride forms. U.S. Patents which describe such compounds and the like include Nos. 3,652,645; 3,784,635; 3,873,302; 3,983,168; 3,907,866; 3,798,276; 3,928,416; and 4,063,929. Published European Applications 3416 and 23,292 disclose N-sulphonyl-3-phenoxybenzamide derivatives and their salts are herbicides.